Has anyone recovered a powerbelt from an animal, geletin, etc that was essentially intact?

My question for you is: are there rifling marks on the bullet?

The reason I ask is that I went out shooting both T/C maxiballs, Hornady great plains, and powerbelts last weekend from my Omega.

The maxiballs, and great plains bullets made holes in a paper target and its cardboard backing NOTICABLE bigger than the powebelts. I realize that they are made slightly underbore size, but I understood that when the powder goes off, they expand to full bore and engage the rifling.

However, if that is true, then why don't they make as big a hole in the taget.

I did not measure the holes, but it was real obvious with the naked eye which holes were the powerbelts.

Therefore, I got to wondering if they really expand and engage the rifling at all. If so, then there is some other explaination for the size difference. Probably the fact that full bore lead conicals are made slightly overbore to engage the rifling BEFORE you fire. Didn't think it would be that noticable on the paper though.

Just curious.